Joseph cbanteux



J. CHAN'EUX.

SCREEN FOR CINEMATOGRAPH PRUJECTIUNS Mm OTHER SIMILAR PROJECTIONS.

MILlcnnon man Mmc. 2. 1911.

JOSEPH C-HANTEUX, 0F BRUSSELS, BELGIUM.-

SCBEEN FOR CINEMATOGRAIII PBDJECTIONS ANI) OTHER SIMILAR PROJECTIONS..

specification of Letters Patent.

Patented Sept. 9,- 1919.

Application mea mmh 2, 1917. serial no. 152,153.

To all 'whom it may concern:

, Be it known that l, JOSEPH CHANTEUX, a subject of the King of Belgium,residing at Brussels, in the Kingdom of Belgium, have invented certainnew and useful Improvements in Screens for Cinematograph Projections andother Similar Projections, of which the following is a specification.

This invention relates to a screen for cinematograph projections andother similar projections.

Screens for cinematograph projections and the like, as hitherto used,have generally been formed of a piece of white linen-cloth. Experienceshave shown, however, that such a screen gives but a very haddistribution of light, causingin practice a great loss of light andconsequently of electric energy.

Therefore, it has been propos in order to reduce the electric energyrequired by the source of light, to use metallized screens, that is tosay screens in which the projecting surface is covered with alight-reflecting coating adapted to reduce the loss of light. Screens ofthis kind do not give either satisfactory results as indeed they do notsecure a distribution of light corresponding to the several cases of thepractice that is to say a repartition of light adequate-in eachparticular case-to the special dimensions of the room; generallyspeaking the pictures are confused7 without relie` and the contrastbetween the white and the black parts of the pictures is greatlydiminished for the spectators whose visual rays fall uponthe screenunder an angle which is notably less than 90. f

On account of this inconvenience it ha further'been proposed to reducethe lightreflecting power of metallized screens by aid of a layer ofglass pearls, said pearls being iixed upon the metallic coating by aidof a suitable adhesive. This expedient however has an important drawbackas, indeed, the glass pearls produce on thesurface of the screen amultiplicityo projections between which dust accumulates very rapidly insuch a manner that.- in a very short time, the screen is deprived of anyelicient lightreiiectino' power. l

One dhject of my invention Ais to avoid these inconveniences; anotherobject is to secure, so to say, in each special case, surfaces of equalilluminating power adapted to utilize the whole space of the room in thebest possible conditions. In other words my invention has for itsobject, while retaining the advantages of a metallized screen with aview of reducing the consumption of electric energy, to secure a betterdistribution of light than hitherto in such a manner that each spectatorreceives approximately the same quantity of light (in view of thedimensions of the room) without however that .this advantage beannihilated by the incon veniences which are due to the use of screenscoated with a rigid material forming prejudicial projections. `Y

With this object in view my invention consists .in combining in a screenthe favor able eiects of a light-reflecting material or medium with thespecial eiiects of a lightdiiiusing material or medium applied on thescreen in a smooth and even coating. ln these conditions thelight-diiiiusing medium or material, without interfering with theprincipal qualities of the screen, reduces the action of thelight-reiiecting material or mediumbut increases the diusion of lightfor the spectators who, otherwise, should be placed under an unfavorableangle relatively to the screen.

Further, it is possible, by a suitable repartition or distributienet thetwo materials, that is by their combination in special conditions, toreduce or to increase the eiiects ofone or the other of the twomaterials and to secure a distribution of light specially adapted toeach case.

In practice, such a combination of the two materials (light reiiectingmedium and light-diffusing medium) can he obtained by superposition orby the production of spots, streams or streaks by means of differentcoatings, said coatings being partly of lightrefiecting material andpartly of light-diffusing material.

ln order to have my invention fully un derstood I will hereafter fullydescribe the several operations required for the preparation of a screenaccording to my invention.

In the accompanying drawing the figure thereof shows a fragmentarysectional view of a screen embodying my invention.

lll

A piece of linen, A, prepared as usual-lor oil painting is covered witha coating B ot' the following composition;

This coating is applied with a brush and is then immediately plugged soas to renim-e any streak resulting' troni the appli'- cation with thebrush. Before complete drying of this layer, that is to say while it isstill more orless sticking or adheringr a light reflecting material ormedium C such Vas aluminum powder for instance, or any other suitablemetallic powder, is applied thereon in an even layer. W'hen the metallicpowder adheres rinly to the screen, after complete drying of thecoa-ting, a solution ot a light-diusing material orinediuin D isprojected on the reflecting surface, for instance by aid of anatoiniaer, said solution lacing composed as an example ot white gum andsilver-white in the proportion ci 25 gr. of White gum and of 5 to 25 gr.of silver-White for a liter ot water.

The projection of this solution produces, upon the light. rellecting;coating, a hind of spotted deposit, the character of which raries withthe duration vof action ot the atomizer. Spots of various forms orshapes and size can thus be. produced on the surtace of the screen. lnthis way various combinations of the edects ot the lightretlectingmaterial and ot' the light-didusing material' nia-y be obtained.

As indicated, the vlayers ot light redecting and light-diusing materialare separately applied. In this way I am able to provide the screen witha redecting surface which extends over the entire area of the screen,and which reflects substantially the entire quantity of light receivedfrom the projecting apparatus. But as the light necessarily passesthrough the layer of dil'usingr material, the rays are diffused and thestrong glare is modified, and the light is transmitted from the screenin, all directions. The images of the pictures projected upon the screenare thus clearly observable in all parts of the room or auditorium inwhich the screen is used, and by all beholders, irrespective of theirangle of Vision upon the screen.

It will he observed that the screen, which is thus produced is reelromindia-rubber and consequently from the Well known inconveniencesconnected with the use of surfaces treated with india-ruhloer;V thelayer produced by the solution applied on the linen -cloth isdiaplianous and possesses au ambered appearance having consequently a YLoraine of the light-diusing medium with regards to the distrihution ollight, the parts or' the pictures which illuminated, are perfectlywhite. @n the other hand, the darli parts ot the pictures are perfectlylolacl: ou -account of the grayish color oi the screen Whereas thewhiteparts scintillate in the light; the contrasts are very icron-Duneedand gire a. perfect relief to the pictures.

My invention is obviously not restricted the special compositions ofcoatings hereinhei'ore described. lnstead or the products which hat/eheen cited, other equivalent prodnets can he used if they are adapted togire similar results. Thus, for instance, in the rst'layer or coatingtor the light-renewing medium, the poppy oil, which is used in order tofacilitate the use of Holland oil, could he replaced by another oilsecuring the saine result.

Further, instead ot yellow ocher, any other material hzsoiinfg a similarcolor, could also he used. The combination oi the two materials (thelight-reliecting medium and the light-diffusing medium) could also beproduced in any other manner. .s an enanaple, the reectiug material(metallic powder) could he applied on the rst layer or coating in thetorni ot' a pasty coating. This can he 'ohtained hy mixing aluminumpowder, tor instance the proportion ot l0@ grs. with the followingcomposition:

Brown varnish 9.200 lit. Siccatire drier 0.300 Turpentine 6.300

Sil

a brush and then immediately plugged. llhe light-didusing coating isthen applied as al-v ready described hy means ot an atomizer. lncertain. cases, the light-reecting coating could also he a plied in theform oi' spots, streams or strea s upon a layer oi light-ditfusingmedium or this latter could he afpplied in the forni oil? a uniform andtransparent layer ,upon the coating of light-re- `llecting medium. Thebase upon which the layers or coatings are applied need not necessarilyhe a linen-cloth. Any other suitable hase could also he used Withoutdeparting from the scope .of my invention provided said hase he covered"by superposed layers et a light-reliecting material or medium and of alight-didusing material or medium, giving' to the screen a smooth andeven surface.

What l claim is:

L 'A screen for cinematograph and similar projjections, comprising ahase, a coating ol llfrhtredectlng material applied to the tace of saidbase, and a second coating of light diffusing material independentlyapplied to said coating of reflecting material in the form of spots orstreaks.

2, A, screen for cinematograph and similar projections, comprisingr abase, a coating of light reflecting material applied to the face of saidbase, and a smooth coating of light diffusing material applied to theface of the first said coating in the form of or streaks.

A screen for cincmatograph and similar projections comprising'a base, alayer of metal powder applied to saidV base by a paint-like coating of acolor which is com* plemental to the color of the met-al powder, and asmooth coating of light diffusing material superposed on said layer ofmetal powder,

4. A screen for cinematograph and similar projections comprising a clothbase prepared as usual Jfor oil painting, a layer of metal. powderapplied to said base by a coating of oil, siccative drier and coloringmatter which is complemental to the color of the metal powder, and acoating of light diiusing material over the layer of metal powder.

spots 5. A-screen for cinematograph and similar projections, comprisinga base, a layer of metal powder applied to said base, by paintlikecoating of a color which is complemental to the color of the metalpowder, and a smoothcoating of light diffusing material applied to thelayer of metal powder in the form of spots or streaks.

6. A screen for cinematograph and similar projections comprising a clothbase prepared as usual for oil paintings, the said base having a coatingthereon composed of Holland oil, siccative drier and yellow ocher andhaving a metallic powder applied to said coating to produce alight-reecting surface, and a light-diffusing coating composed ofWhite'gum and silver White applied to the light-reflecting surface inthe form of spots or streaks.

In testimony whereof I have aixed my signature in presence of twowitnesses.

JOSEPH GHANTEUX.

